84 results about "Ionization detector" patented technology

A design and readout of a xenon detection medium based device, which provides improved spectroscopic performance compared to currently commercially available devices. To achieve energy resolution improvement, a method to accurately measure radial spatial position for interacting events within a HPXe cylindrical detector is described using the plan as shown in FIG. 4. This is accomplished by utilization of light generated both at the gamma interaction site and at the collection point near the anode wire of the cylindrical detector. These light flashes are detected by a VUV photon detector. Light transmission is facilitated by incorporating a vacuum ultraviolet (VUV) light transparent window at least one end of the cylindrical ionization detector. With the known electron drift velocity in HPXe, the time between these two photopulses is sufficient to accurately determine the radial coordinate. Consequently, correction by electronic means for the electrostatic pulse dispersion using the expression graphed in FIG. 2 can be achieved in order to approach the true intrinsic energy resolution limit for HPXe.

Applicant's present invention comprises mass spectrometer systems that operate in a mass range from 1 to 1016 DA. The mass spectrometer system comprising an inlet system comprising an aerodynamic lens system, a reverse jet being a gas flux generated in an annulus moving in a reverse direction and a multipole ion guide; a digital ion trap; and a thermal vaporization / ionization detector system. Applicant's present invention further comprises a quadrupole mass spectrometer system comprising an inlet system having a quadrupole mass filter and a thermal vaporization / ionization detector system. Applicant's present invention further comprises an inlet system for use with a mass spectrometer system, a method for slowing energetic particles using an inlet system. Applicant's present invention also comprises a detector device and a method for detecting high mass charged particles.

A nondestructive testing method of condensed matter surfaces, and a sensing device for the measurement of the work function of the surface of a conducting or semiconducting sample. The sensing device includes an ionization chamber, a probe having a first surface, and a potential difference measurement circuit that is capable of measuring a difference in potential between the first surface of the probe and a surface made of another material to be tested. The ionization chamber produces ionized particles that travel out of an output of the ionization chamber and toward the probe. The probe is a non-vibrating probe having a first surface that is either a positively or negatively charged electrode. The measurement circuit of the present invention is capable of sensing the small amount of electrical current that the electrons and ions moving toward the first surface and the testing surface represent.

This invention publishes a kind of gas phase chromatography method which can measure the air content and the specific gas in the insulating oil with just once sampling. This invention uses Ar as carrier gas. It also uses the packed column sample entrance. What is more, it has six-way value color-spectrum-switching column, heat transmission detector and the H-fire ionization detector. During the process, Ar is divided into 2 parts. One part will directly go out after it goes through the heat transmission detector's reference arm 6, while the other part will go by steps through the sample entrance 1, the first color spectrum column 2, the six-way value 4, the second color spectrum column or gas lock 3, the heat transmission detector 7, the Ni catalysis CH4 converter 8 with H2, and at last the H fire ionization detector 9 with the air. Then it will go out. During the only one sampling, the invention can meanwhile measure the air content and analyze the accident specific gas in the simple oil. To sum up, it operates easily, needs little work and can decrease the analysis error relatively. So it can do the work of analyzing the sample oil which has low degassing ratio well, as it can satisfactorily separate all the groups.

An instrument for checking quality of therapeutic x-ray and electron radiation provides modes optimized for both electrons and for photons obtained by physically flipping the unit to interpose the necessary build-up material between the radiation beam and contained detectors. The invention provides an improved method of constructing ionization detectors for improved energy discrimination using such detectors and wire-free operation.

The invention relates to a method and apparatus for determining the intensity distribution of a radiation field. In the method, the ionization caused by the radiation field is detected by parallel ionization detector planes arranged in an ionization chamber, two of which planes are formed of series of wires determining the position of an ionization event in the X and Y directions, which detector planes provide the X and Y co-ordinates X1, Y1 of the ionization event. The ionization event is created by photonuclear reaction products arising from the radiation.

A driver provides a current through a load circuit that includes an ionizable path. The driver includes an energy sourcing circuit, an ionization detector, a controller, and a pulse generator. The controller determines, in response to the detector and by trial and error, a respective quantity of energy for each pulse of a plurality of pulses to be generated. For each pulse of the plurality, the pulse generator receives the respective quantity of energy from the energy sourcing circuit, provides in response to the quantity of energy a respective voltage to ionize the ionization path, and provides the current through the load circuit.

A photoionization detector includes a housing, electrical contacts within the housing and an easily removable and replaceable photoionization chamber within the housing. The photoionization chamber includes a cathodic electrode and an anodic electrode which may be coated with a thin layer of material. The photoionization chamber and the associated cathodic electrode and anodic electrode are removable from within the housing as a unit. The photoionization chamber makes electrical connection with the contacts when seated within the housing regardless of the orientation of the photoionization chamber about an axis.

A method of gas analysis and an ionization detector for its implementation provide a qualitative and quantitative analysis of impurities in a main (buffer) gas. The detector can operate in a wide range of gas pressures, up to atmospheric one. The identification of impurities is provided by analyzing the energy of electrons produced by the ionization of the impurity atoms or molecules in their collisions with long living atoms of a buffer gas or with monochromatic photons. The energy analysis of electrons produced in the collisions of impurities with metastable atoms in the afterglow plasma ignited between two plane electrodes is performed by determining the second derivative of electric current dependence on the voltage applied between the anode and the cathode. The electron energy can also be analyzed by positioning a grid between the anode and the cathode and by using an external ultraviolet radiation source to ionize the impurities in the equipotential space between the grid and the anode. The inter-electrode gap and the gas pressure are chosen in such a way that the distortions in the electron energy measurement due to the collisions with the gas atoms or molecules should not exceed a prescribed value.

A new design for a cylindrical ionization detector, featuring a resistive cathode, and external pickup wires that sense both the azimuthal and radial coordinates of interaction vertices. Combined with measurement of the longitudinal coordinate (using resistive anode wire charge division or other technique), the proposed design can provide an accurate 3-dimensional imaging detector and offer improved spectroscopic response.

An auto-cleaning and auto-zeroing system (1) comprises a first conduit for flow of ambient gas (16) and a 2nd conduit (22) for flow of ambient air (18). A cleaning chamber (12) removes impurities from ambient air (18). The 1st conduit (20) and 2nd conduit (22) are connected to a valve, operated by the continuous motor, which continuously draws ambient gas (16) or cleaned and filtered ambient air (18) through the system. Cleaned and filtered ambient air (18) enters the ionization chamber (10) to carry out a cleaning (flushing) and a cleaning (ionization) cycle. In this manner, contaminants and pollutants left in the ionization chamber (10) from the measurement of ambient gas (16) are flushed out and removed.

A driver provides a current through a load circuit that includes an ionizable path. The driver includes an energy sourcing circuit, an ionization detector, a controller, and a pulse generator. The controller determines, in response to the detector and be trial and error a respective quantity of energy for each pulse of a plurality of pulses to be generated. For each pulse of the plurality, the pulse generator receives the respective quantity of energy from the energy sourcing circuit, provides in response to the quantity of energy a respective voltage to ionize the ionization path, and provides the current through the load circuit.

The present invention provides a bias generation circuit in which the voltage of electrically isolated circuits are stabilized by providing a photovoltaic diode in each circuit, a common light source uniformly positioned to provide equivalent energy to each photovoltaic diode and an operational amplifier, configured with a capacitor as an integration circuit, driving the common light source, wherein one isolated circuit provides feedback to the amplifier, such that variations in the voltage in the isolated circuit causes the amplifier to provide an adjusted signal to the common light source, adjusting the energy output to compensate for voltage variations simultaneously, yet independently occurring in each isolated photovoltaic diode circuit. Such bias voltage circuit may be used with chromatographic ionization detectors as well other devices.

A system and method for ionization detection in electrically enhanced air filtration systems is described. One embodiment includes a system for electrically enhanced air filtration, the system comprising an electrically enhanced filter comprising a filter and an ionizing electrode disposed on an upstream side of the filter; a control device connected to the electrically enhanced filter, wherein the control device can control the electrically enhanced filter; and an ionization detector, wherein the ionization detector is adjacent to the electrically enhanced filter and wherein the ionization detector is connected to the control device.

The present invention provides a bias generation circuit in which the voltage of electrically isolated circuits are stabilized by providing a photovoltaic diode in each circuit, a common light source uniformly positioned to provide equivalent energy to each photovoltaic diode and an operational amplifier, configured with a capacitor as an integration circuit, driving the common light source, wherein one isolated circuit provides feedback to the amplifier, such that variations in the voltage in the isolated circuit causes the amplifier to provide an adjusted signal to the common light source, adjusting the energy output to compensate for voltage variations simultaneously, yet independently occurring in each isolated photovoltaic diode circuit. Such bias voltage circuit may be used with chromatographic ionization detectors as well other devices.

Nested ionization chambers provide independent measurements of a radiation beam that does not fully irradiate the volume of one or both chambers. By mathematically combining these independent measurements, partial volume effects caused by a change in ionization detector calibrations when the full detector volume is not irradiated by the radiation beam, may be decreased, providing more accurate measurement of extremely small radiation beams.

The invention includes an ionizing radiation detector which includes a chamber within a housing. A receiving member within the chamber has a plurality of spaced holders for receiving samples. The samples are maintained in an array of substantially parallel samples with the samples functioning as electrodes within the chamber. The invention includes a method of counting emissions from samples. An odd number of electrodes are introduced into a detector chamber. Each of the electrodes includes at least one sample to be analyzed. The electrodes are organized into an array of substantially parallel electrodes, each electrode being in electrical communication with a contact surface. The electrode array includes cathodes and anodes where the number of cathodes differs from the number of anodes by one. A voltage is applied across the electrodes and particle emission is detected from the samples based upon ionization of counting gas within the chamber.

The invention relates to a bidirectional pulse ionization detector. The bidirectional pulse ionization detector is a device used for defining the composition of a gas mixture. The device and the chromatograph are used together to analyze the composition of the sample gas. The detector comprises an integrated examination pond, a monolithic processor, a pair of discharge electrodes, a polarized electrode and a collecting electrode. A stable bidirectional pulse high-voltage power provides the pulse voltage for the discharge electrode. The monolithic processor controls the pulse width, cycle and pulse height of the monolithic processor. The polarized electrode and the collecting electrode produce an electric field under the control of a DC voltage, and collect the electron or ion in the electric field. A collected electric current outputs a voltage signal after the collected electric current is enlarged by an electrometer. The ionization detector is characterized by general utilization, high sensitivity, no radioactive source, non-destructiveness, no open flame, etc. The ionization detector has the widespread use.

The invention provides a high-energy X-ray industrial CT ionization detector, which can overcome the defects of scintillator detectors and is suitable for radiation detection of a high-energy X-ray industrial CT system. The detector comprises seal housing which is filled with working gases and is provided with a plurality of ionization chamber units; the ionization chamber unit is elongated and comprises a U-shaped ionization chamber wall and a latten; a receiving terminal of the X-ray on the latten is fixedly arranged at an open end of the U-shaped ionization chamber wall via an insulation sheet; the other end of the latten is arranged in the ionization chamber and spread along the length direction of the ionization chamber; the latten, with thickness less than or equal to 0.3mm, is manufactured by high-density metals with high atomic number or the alloy of the metals; a coat on which secondary electrons are easily generated covers the external surface of the latten; the U-shaped ionization chamber wall is connected with a signal processing circuit as a collector; the latten is connected with a high-voltage cathode and a high-voltage power supply as a radiation converter.

The invention discloses a high-purity nitrogen trifluoride analysis oxygen-free adsorption gas chromatography valve path system and a use method thereof. The valve path system using four valves and four posts comprises two four-way valves, two ten-way valves, two quantitative rings, four chromatographic columns, 11 pressure balance regulating valves and one discharging ionization detector. The system carrier gas is high-purity helium with the purity higher than 99.9999 percent. The system has the advantages that simplicity is realized; the operation is convenient; the analysis is accurate.

The invention relates to a foul gas detection device based on a micro-fluidic chip. The foul gas detection device comprises a gas path system, a control system, a gas detection system and a data processing system, wherein the control system adopts a temperature control system; the gas detection system adopts a light ionization detector; the foul gas detection device is characterized by further comprising a sample injection system and a gas separation system; the sample injection system is connected with one side of the gas path system and one side of a gas separation system respectively through a left connection piece and a right connection piece; the control system is arranged on the lower part of the gas separation system; the other side of the gas separation system is connected with the gas detection system and the data processing system in sequence; the gas separation system adopts the micro-fluidic chip, wherein a fixed phase coats inside of a micro channel of the micro-fluidic chip; the sample injection system comprises a sample gas inlet, a connection piece, a quantification pipe, a three-way valve, a two-way valve and a diagram pump. The foul gas detection device can accurately and effectively control pressure of a gas path, and is stable in flow and high in detection precision; full separation of multi-component gas can be realized, so that qualitative and quantitative analysis on the multi-component gas is realized.

The present invention provides an ionization detector having a base having an enclosed chamber. The enclosed chamber has a first end and a second end. The detector also includes a first outlet which is a source of an excitable medium. A second outlet is provided which functions a source of an analyte that is transported by a carrier gas. An ionization source for creating a discharge from said excitable medium is also provided. The collector electrode generates a time dependent current based on its interaction with ionized analytes from which the analyte may be detected.

To suppress baseline current other than baseline current derived from the ionization of impurities, and to achieve the enhancement of the SN ratio of a detection signal and the improvement of the lower limit of detection, the inner diameter of a bias electrode for collecting an ion derived from a sample component is made smaller than the inner diameter of an insulating member separating the bias electrode and a collector electrode. Light emitted from plasma formed by dielectric barrier discharge is shielded by the bias electrode, so that the light is not cast directly on the surface of the insulating member. Therefore, the photoelectric effect caused by casting light of high energy does not occur on the surface of the insulating member, whereby a decrease in electric resistance of the surface can be prevented.

An instrument for checking quality of therapeutic x-ray and electron radiation provides modes optimized for both electrons and for photons obtained by physically flipping the unit to interpose the necessary build-up material between the radiation beam and contained detectors. The invention provides an improved method of constructing ionization detectors for improved energy discrimination using such detectors and wire-free operation.

The present invention refers to a surface ionization detector comprises an emitter, a heating rod, a collecting electrode, a reducing liner and a housing. The emitter is made of molybdenum, platinum or alloy, and in the form of cylinder or a wire spiral. The heating rod heats and supports the metal emitter. When the heating rod is heated to 300-500° C., organic amine compounds collide with the surface of the emitter, generating positive ions through surface thermal ionization and thus are detected. The lowest detecting limit value of tertiary amine by the detector in the present invention can achieve to 10−14 g / s. The response to other hydrocarbons, ketones, etc., is 5-6 orders of magnitude lower than that of organic amines. The detector can selectively detect amines, hydrazines and their derivatives, and so on. The detector can be used as a detector for a gas chromatography system adopting capillary column or packed column, or alternatively be used alone as a sensor.

Sodium-cesium detection systems and methods for the simultaneous detection of both sodium (Na) and cesium (Cs) in gas are provided. The detection systems include two non-identical ionization chambers each having an anode and a cathode that ionize Na and Cs in gas. Each ionization chamber generates a current proportional to the Na and Cs concentration and based on the current, Na concentration and Cs concentration in the gas is determined.

An apparatus for interfering with locomotion of a target by conducting a current through a load that includes an ionizable path. The apparatus includes, according to various aspects of the present invention, an energy source, an ionization detector, a charge detector, a controller, and a pulse generator. The controller determines, in response to the detector and by trial and error, a respective quantity of energy for each pulse of a plurality of pulses to be generated. For each pulse of the plurality, the pulse generator receives the respective quantity of energy from the energy source, provides in response to the quantity of energy a respective voltage to ionize the ionization path, and provides the current through the load. The charge detector detects a charge provided through the load. The processor sets the voltage for charging for a next pulse in response to the charge detected by the charge detector.